Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

These are the sounds issued forth from my beloved Tecumseh engines equipped with fixed Jets. I don't own one but my friend does on a machine I recomended and he constantly rags me about it. In an effort to get him off my back I have researched the following and these are the results:

1) The replacement carb for a medium frame Tecumseh is 632334A ( this is a part # that replaces a disontinued part but the blow up diagram of the replacement shows an adjustable main jet. Therefore I ASSUME it is adjustable.

2) The carburetor repair kit for this model is 632347 

I was able to secure a blowup diagram of this carb and the list of parts in the repair kit. It APPEARS all of the main jet parts are present in the kit.I NEED VERIFICATION If this includes the needle and the jet. 

If one were to remove the fixed jet from the current carb which I believe is the green plastic tube held in by O-rings and replace it with the adjustable jet and needle from the #632347 repair kit would it work? Could you retrofit the new bowl with the adjustable assembly or would you have to buy a new bowl?

If anybody could verify or correct my assumptions I would be most appreciative.

Marc

Just for the record -theHonda GX series engine on my power washer made the same spit, sputter,cough,blemph sounds due to it's fixed jet carb. Honda has addressed this problem by producing a line of altitude related jets. Another words if you want to richen up a Honda fixed jet carb parts are available. The carb will still be fixed jet but at a richer setting.

 Richie,

 Thanks for the numbers.

Also when you were at the Tulsa engine site, did you check the specs on the Tec HMSK 8, graph shows about 6.4 HP out of 8.

The 10 shows 8HP, which is about a 20% loss due to the EPA carb.

I think that your good carb got you back at least 1 HP,  maybe more, so now your 8 is at least about 7.4HP.

                                                        Fred  

jubol wrote:

Fred,

I'd have to verify the graph you are referring to, but I believe that is the one I have.  As for additional HP due to my adjustable carb, it stands to reason something good came out of it, beyond the fact it runs better, but what makes me hesitant about me commenting further is the fact these engines run at a governed speed.  For whatever it's worth, if I had to do it all over again, I'd still make the carb switch

Marshall, if you were referring to me in the way I answered Fred's previous question about HP verses the new carburetor, thanks.

I was sir, and you're welcome!

What is also fish about that tulsa site they will only give you one full graph of the hp to torque chart per category of same cube engines  I.E. are both 19.43 cubes.  so no graph on the nine.  Strange also important to notice two reference points on the graph,  operating rpm on my 8 hp is 3600, under load it can drop to 2800.  at 3600 it developes 11.5 ft pounds of torque and at the lower rpm it increases to 12.9 foot pounds.  however it looses the meaningless HP number as it decreases by like 1.25 hp  .. Torque is much more important ref  here and it is what is keeping the engine runnin under load Would be willing to bet the nine developse it's hp at a higher rpm above 3600 and it could be very well the same engine  that has the same torque at the 3600 and the 2800 rpm's  .  bore an stroke are the same cept seems they decided to write one of them in decimal and the other in SAE.  same weight to the motor etc,  everything they do always looks like a shell game. 

If it looks like a duck

an walks like a duck,

maybe it is a duck

Ben07 

What's the difference in price on the 8 & 9 HP?

Oh, you guys have a link to the 8-9-10,etc. HP engine charts?

Can't give it you exact Marshall, cause it is kind of mixed up in a hodge poge, as they do not have all the engines for sale, so you can't actually compare an hmsk 8 to an hmsk 9,  you can get a generathought though, but different engines have diff bolt-ons,  like air cleaner no aircleaner, some fixed linkage with a governor  and others no fixed linkage, say for like a go cart etc. 

But in general seems to go from like 400 to 460 in the average diff between 8 and 9  would more research to get better info,  will prob be unavail to do that  at this time    just tryin to give you a general feel etc.

(also remember you go from an 8 to a nine on a SB  an there could be hundreds of dollars diff,  but some of that is extras, like drift cutters, heated grips , lil wider auger box..

 I am not talking things like differentials 

1120 1457

Like on the ariens deluxe line the 8.5 is 1.120 dollars and the 11 is 1457  (no differential on either

Ben07 

Thanks Ben, I do appreciate it!

Well, that's not too bad if it's around 60 bucks. Even if I spent an extra 75 for a 1/2 HP, I wouldn't be upset if it's a true 1/2 HP.

Ben07 wrote:
Down shifting has less to do with horsepower and more to do with a multiplication of torque. Not anything like a govenor.

hey guys ...

all a governor is supposed to do is maintain i desired speed.

if your engine is set at 3600,the governor will try to maintain that same 3600 rpm regardless of load.if your engine drops to 2800 rpm i would say thats too much of a drop.either go down a gear or have a look at your governor settings.somthing aint quite right.

not trying to upset anyone but this is my job here and i wouldnt be happy with an 800 rpm drop.it should work better i would like to see it go no lower than 3200 for an engine speced out at 3600.

now just to mix it up a bit when i was looking at torque charts some engines are set at 3750 max rpm...yikes that scares even me.

the torque peak of all the tecumseh engines i looked up was right in the 2450 to 2550 range and it was a broad flat curve.

another interesting that i noted was cubic inches of displacement. there math is not good.

if you look at the bore and stroke ,some have smaller bore with same stroke and still have same displacement.

its not quite right to me.

there is a note in the fiche cards about pistons,you have to measure old one to get correct replacement,there is up to 1/4 inch difference in diameter on same size engines.

later chris 

You know, this I agree with whole heartedly.

I would say that if the engine is dropping that much it is either not right or you don't have enough engine for the job at hand. If an engine is constantly running in the 2800 RPM range because of the amount of snow, you either need to push less snow at a time or need more engine to handle the amount you're blowing. Snow, grass, 600 lb man in a go-cart  ,anything.